Imprints of pandemic lockdown on subsurface water quality in the coastal industrial city of Tuticorin, south India: A revival perspective
Autor
Selvam, S.
Jesuraja, K.
Venkatramanan, S.
Chung, S.Y.
Roy, P.D.
Muthukumar, P.
Kumar, Manish
Institución
Resumen
Globally, incidences of environmental improvements owing to seizing the anthropogenic
activities during the lockdown have been reported through news articles, and photographs,
yet a formal scholarly study has been lacking to substantiate the imprints of lockdown. We
hereby present the imprints of lockdown period on water quality (both chemical and
biological) parameters during the nationwide lockdown (COVID
-19 epidemic) in India
between 25th March to 30th May 2020. The present study describes the changes in chemical
and biological water quality parameters based on twenty
-two groundwater samples of a costal
industrial city of Tuticorin in Southern India, taken before (10
-11th February, 2020) and
during the lockdown (19
-20th April 2020) periods. Parameters compared are pH, total
dissolved solids (TDS) and electrical conductivity (EC), nitrate (NO
3), fluoride (F),
chromium (Cr), iron (Fe), copper (Cu), zinc (Zn), cadmium (Cd), lead (Pb), arsenic (As), and selenium (Se); and bacterial parameters like total coliforms, fecal coliforms, E. coli, and
fecal streptococci
. Among the metals, the significant reductions in Se (42%), As (51%), Fe
(60%) and Pb (50%) were noticed probably owing to no or very less wastewater discharges
from metal
-based industries, seafood
-based industries and thermal power plants during the
lockdown. Reduction in NO
3 (56%), total coliform (52%) and fecal coliforms (48%)
indicated less organic sewage from the fishing industries. Contents of Cr, Cu, Zn and Cd,
however, remained similar and fluoride did not show any change, probably as they were
sourced from rock
-water interactions. Similarly, we did not observe alterations in E. coli and
fecal streptococci due to no significant change in domestic sewage production during the
lockdown. Finally, the multivariate analyses aptly illustrate that while principal component
analyses identify different four sources operating in the area, the difference among the
different water qualities start diminishing during the lockdown. The study implies that
groundwater is definitely under active interaction with surface waters and thus a quick revival
could be observed following the seizing of anthropogenic activities during lockdown.